The contract title is "Resynthesis of Potential Therapeutic Agents for Treatment of Infectious Diseases". The objectives of this contract is as follows: l- The chemical resynthesis of potential therapeutic agents to treat infectious diseases. These resynthesized compounds will be used in: cell culture assays, biochemical assays, animal models, pharmacological disposition studies in laboratory animals and toxicological investigations, and to permit preparation of pharmaceutical dosage forms for clinical evaluation. The Contractor will be requested to scale up and/or modify synthetic procedures to yield increasingly larger batches of therapeutics (approximately 5, 100 and 1000 gram/lots) as required to support the Government's ongoing evaluation of these agents. The Project Officer will identify the target materials and provide synthetic methods when available. When no synthetic route or specific procedure is provided by the Project Officer, the Contractor shall propose one for the Project Officer's approval prior to starting work. 2- Acquisition, through purchase or donation, compounds for efficacy testing against opportunistic pathogens (e.g. Pneumocystis carinii,Mycobacterium avium complex, Toxoplasma gondii, etc) associated with AIDS. The chemical resynthesis is the main effort under this contract.